1. Field of the Invention (Technical Field)
The present invention relates to an apparatus for feeding bulk carbonaceous material, such as chips of used automobile tires, to a destructive distillation unit while sealing against exchange of ambient air and distillation gases through the feeding system. More especially, the present invention relates to a feeding apparatus which permits the feeding of comparatively low-density feedstock material through the liquid seal.
2. Background Art
One of the inherent problems in the art of destructive distillation of carbonaceous solids, such as bulk chips of automobile tires, is to accomplish effective feeding or charging of the distillation unit. The problem is compounded when one attempts to feed bulk solid materials to a continuously operating still while maintaining a seal between the atmosphere and the still such that flammable gases from the destructive distillation process do not mix with oxygen-containing gases, such as atmospheric air, which results in damaging explosions and fires in the still and feeding system.
The present disclosure is related to the device disclosed in U.S. Pat. No. 5,714,043 to Finley et al. The '043 patent was co-invented by the present Applicant, and solved many of the afore-mentioned problems associated with supplying feedstock into a distillation system while reliably isolating the pyrolytic chamber from the ambient atmosphere.
A significant potential drawback to the device of the '043 patent, however, is its inability to reliably feed low-density material into the distillation system. The device of the '043 patent to Finley et al. employs a liquid seal to isolate the pyrolysis chamber. The '043 device relies nearly exclusively on gravitational forces to move the feedstock through the liquid seal. Thus, only feedstock having a density exceeding the bulk density of the liquid in the seal reliably sinks through the seal to then be mechanically conveyed toward the pyrolytic camber(s). This circumstance may pose difficulty when the liquid is heavy (e.g. oil) and the feedstock is comparatively lightweight waste (such as chipped computer circuit boards, for example).
Also, it has been determined that the device of the '043 patent may not adequately regulate the introduction of feedstock, resulting in the binding of the auger and other problems. The use of a simple continuous feeding mechanism, such as the horizontal screw conveyor of the '043 patent, permits irregular, marginally controlled, “lump” insertion of feedstock. It is desirable better to coordinate the timing of the feed with the operation of the feed auger that moves the stock through the liquid seal.
The present invention marks a significant improvement to the system seen in U.S. Pat. No. 5,714,043 to Finley et al. According to the present disclosure, feedstock materials can be reliably and safely fed through the liquid seal of the apparatus, regardless of their density.